RS-08-010, Additional Information Supporting Request for Amendment to Technical Specification 5.5.16, Containment Leakage Rate Testing Program

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Additional Information Supporting Request for Amendment to Technical Specification 5.5.16, Containment Leakage Rate Testing Program
ML080320555
Person / Time
Site: Byron, Braidwood  Constellation icon.png
Issue date: 01/31/2008
From: Simpson P
Exelon Generation Co, Exelon Nuclear
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
RS-08-010
Download: ML080320555 (9)


Text

Exel6n Nuclear Exelon Generation www.exeloncorp .com 4300 Winfield Road Warrenville, I L 60555 RS-08-010 January 31, 2008 U. S. Nuclear Regulatory Commission ATTN : Document Control Desk Washington, DC 20555-0001 Braidwood Station, Units 1 and 2 Facility Operating License Nos. NPF-72 and NPF-77 NRC Docket Nos. STN 50-456 and STN 50-457 Byron Station, Units 1 and 2 Facility Operating License Nos. NPF-37 and NPF-66 NRC Docket Nos. STN 50-454 and STN 50-455

Subject:

Additional Information Supporting Request for Amendment to Technical Specification 5.5.16, "Containment Leakage Rate Testing Program"

References:

1 . Letter from D. M. Benyak (Exelon Generation Company, LLC) to U. S. NRC, "Request for Amendment to Technical Specification 5 .5.16, 'Containment Leakage Rate Testing Program,' dated April 4, 2007

2. Letter from P. R. Simpson (Exelon Generation Company, LLC) to U. S . NRC, "Response to Request for Additional Information Regarding Request for Amendment to Technical Specification 5.5.16, 'Containment Leakage Rate Testing Program,'" dated October 10, 2007 In Reference 1, Exelon Generation Company, LLC (EGC) requested an amendment to Appendix A, Technical Specifications (TS), of Facility Operating License Nos. NPF-72, NPF-77, NPF-37, and NPF-66 for Braidwood Station, Units 1 and 2, and Byron Station, Units 1 and 2, respectively . The proposed change revises TS 5.5.16, "Containment Leakage Rate Testing Program," to reflect a one-time five-year deferral of the containment Type A integrated leak rate test from once in 10 years to once in 15 years.

Additional information supporting this request was submitted to the NRC in Reference 2. In the Reference 2 submittal, EGC provided references to inservice inspection summary reports, which were previously submitted to the NRC, that provide information related to containment inservice inspections (CISIs) and historic highlights . In recent discussions with the NRC, the NRC requested that EGC provide a summary table that documents significant indications noted during the CISIs and actions taken to disposition the indications. In response to this request,

January 31, 2008 U . S . Nuclear Regulatory Commission Page 2 EGC is providing the attached information for Byron Station . CISI summary information will be submitted to the NRC for Braidwood Station under a separate letter .

There are no regulatory commitments contained in this letter . If you have any questions concerning this letter, please contact Mr. Kenneth M . Nicely at (630) 657-2803 .

I declare under penalty of perjury that the foregoing is true and correct . Executed on the 31 st day of January 2008.

Respectfully, K~A Patrick R. Simpson Manager - Licensing

Attachment:

Summary of Byron Station Containment Inspections

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 2 Spring 2 (IWE) 1 100% penetrations from outside of None 07/31/07 General visual, 2007 the containment (accessible VT-3, and VT-1 by surfaces) certified VT Transfer fuel canal None examiners Two penetrations disassembled in Two bolts with damaged Replaced support of steam generator work threads Moisture barrier (accessible None surfaces) 100% liner including penetrations None (accessible surfaces)

Disassembled equipment hatch None 1 Fall 2 (IWE) 1 100% penetrations from outside of None 01/16/07 General visual, 2006 the containment (accessible VT-3, and VT-1 by surfaces) certified VT examiners Transfer fuel canal None One penetration disassembled None Moisture barrier (accessible None surfaces) 100% liner including penetrations None (accessible surfaces)

Disassembled equipment hatch None 1 and 2 Summer Second -- Exterior containment walls Two hoop tendon grease cans Engineering evaluation was 07/31/07 General visual, 2006 5-year (accessible concrete surfaces (one per unit) exhibited signs performed; dispositioned as VT-3, and VT-1 by concrete including tendon tunnels, of corrosion acceptable . Continues to be certified VT and (IWL) buttresses) enclosed within other monitored on a 20-month VT-C examiners structures frequency. Planned for replacement in 2011 .

Exterior containment walls None (accessible concrete surfaces including dome) exposed to outside Page 1

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 2 Fall 1 (IWE) -- Transfer fuel canal Eight bolts with damaged Replaced 01/10/06 General visuals and 2005 threads detailed visuals equivalent to VT-3 Two penetrations disassembled in None and VT-1, support of Steam Generator work respectively, by Supplemental liner plate at None certified VT elevation 377' examiners Disassembled equipment hatch None 1 Spring 1 (IWE) -- Transfer fuel canal None 01/31/06 General visuals and 2005 06/20/05 detailed visuals Dome liner plate None equivalent to VT-3 Two penetrations disassembled in None and VT-1, support of Steam Generator work respectively, by Disassembled equipment hatch None certified VT examiners 2 Spring 1 (IWE) 2 100% penetrations from outside of None 07/02/04 General visuals and 2004 the containment (accessible detailed visuals surfaces) equivalent to VT-3 Transfer fuel canal None and VT-1, respectively, by Two penetrations disassembled in None certified VT support of Steam Generator work examiners Supplemental liner plate at None elevation 377' 100% liner including penetrations None (accessible surfaces)

Supplemental dome liner plate None 100% moisture barrier None

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 1 Spring 20-year -- Tendons None 01/31/06 VT-1 C, VT-3C, 2004 post- 06/20/05 VT-1, and VT-3 by tensioning certified VT and Wire/strand None (IWL) VT-C examiners Anchorage hardware and None surrounding concrete Corrosion protection medium Replacement grease in excess Engineering evaluation was of 10% in one tendon performed; dispositioned as acceptable .

Free water Water discovered in several Engineering evaluation was tendons performed; dispositioned as acceptable . Continue to monitor .

2 Spring 20-year -- Anchorage hardware and None 01/31/06 VT-1C, VT-3C, 2004 post- surrounding concrete 06/20/05 VT-1, and VT-3 by tensioning certified VT and (IWL) Corrosion protection medium None VT-C examiners Free water None 1 Fall 1 (IWE) 2 100% penetrations from outside of None 01/12/04 General visuals and 2003 the containment (accessible detailed visuals surfaces) equivalent to VT-3 Transfer fuel canal and VT-1, None respectively, by 100% liner plate None certified VT 100% moisture barrier None examiners 2 Fall 1 (IWE) -- Supplemental liner plate at None 01/03/02 General visuals and 2002 elevation 377' detailed visuals Dome liner plate None equivalent to VT-3 and VT-1, respectively, by certified VT examiners Page 3

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 1 Spring 1 (IWE) -- Transfer fuel canal None 06/27/02 General visuals and 2002 detailed visuals Two penetrations disassembled in None equivalent to VT-3 support of Steam Generator work and VT-1, respectively, by certified VT examiners 1 and 2 Summer First 5-year -- Exterior containment walls (all None 06/27/02 VT-1C, VT-3C, 2001 concrete accessible concrete surfaces VT-1, and VT-3 by (IWL) including tendon tunnels, certified VT and buttresses) enclosed within other VT-C examiners structures Exterior containment walls (all None accessible concrete surfaces including dome) exposed to outside

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 2 Spring 1 (IWE) 1 100% penetrations from outside of None 07/19/01 General visuals and 2001 the containment (accessible detailed visuals surfaces) equivalent to VT-3 Transfer fuel canal None and VT-1, respectively, by Three penetrations disassembled None certified VT in support of Steam Generator examiners work 100% penetrations from inside of None the containment (accessible surfaces)

Moisture barrier Moisture barrier degradation Moisture barrier was previously identified in completely replaced Fall 1999 Disassembled equipment hatch None 1 Fall 1 (IWE) 1 100% penetrations from outside of None 01/04/01 General visuals and 2000 the containment (accessible detailed visuals surfaces) equivalent to VT-3 Transfer fuel canal and VT-1, None respectively, by Two penetrations disassembled in None certified VT support of Steam Generator work examiners 100% penetrations from inside of None the containment (accessible surfaces)

Moisture barrier None (Disassembled equipment hatch None

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 2 Fall -- -- 100% penetrations from inside of None 02/11/00 Visual inspections 1999 the containment (accessible per special process surfaces) procedures (SPPs)

Dome liner plate None 100% liner plate None Moisture barrier Moisture barrier degradation Moisture barrier planned for was identified* future replacement in Spring 2001 Airlocks None Exterior containment walls 1. A concrete spall was noted 1 . Repaired on the D-E buttress 2. Repaired adjacent to tendon H13ED*

2. Degraded caulking in one case was identified*

1 Spring 20-year -- Anchorage hardware and None 02/11/00 Visual inspections 1999 post- surrounding concrete per SPPs tensioning (IWL)

Corrosion protection medium None Free water None

  • Note : These indications were not specifically discussed in the ISI summary report . They are included for completeness .

ATTACHMENT Summary of Byron Station Containment Inspections Date of Actions for Summary Method of Unit Date Interval Period Examination Scope Significant Indications Dispositioning Report Examination 2 Spring 20-year -- Tendons None 02/11/00 Visual inspections 1999 post- per SPPs tensioning (IWL)

Wire/strand None Anchorage hardware and None surrounding concrete Corrosion protection medium None Free water None 2 Spring -- -- Metallic containment surfaces and None 08/13/98 Visual inspections 1998 components per SPPs Exterior concrete surfaces None Moisture barrier None